1. Field of the Invention
This invention relates to a voice coil motor.
2. Discussion of the Related Art
Recently, various optical apparatuses have been developed, for example, a mobile phone with a built-in micro camera and a high resolution digital camera.
In case of the micro digital camera adopted to the mobile phone. It was impossible to control a distance between an image sensor and a lens adjusting a magnification and a focus. However, owing to such developments of the lens drive apparatus as the voice coil motor, the distance between the image sensor and the lens could be controlled. In particular, the voice coil motor could control the distance between the image sensor and the lens using a gravitational force and a repulsion force according to an action of magnetic fields generated by a magnet and a coil.
Generally, the voice coil motor is constituted of many components such as a mover, a spacer, and a case, for example, where each component has a manufacturing tolerance since each component is manufactured by each injection molding process or each press process, and therefore, after completion of assembling of all components, the tolerances of the components could not help being accumulated. The accumulated tolerances caused the voice coil motor to raise a problem hard to precisely drive the lens. Accordingly, the voice coil motor had a problem in that its drive operates poorly due to the accumulated tolerances. The voice coil motor had another problem in that the components constructing a voice coil motor are broken or damaged by shocks and/or vibrations transmitted to the spacer, the mover, the stator and the lens through the case from the exterior.